為什么函數(shù)是sortNum而不是sortNum()啊,為什么不加括號呢
<script type="text/javascript">
? ?function sortNum(a,b) {
return b-a;
? ?}
var myarr = new Array("80","16","50","6","100","1");
document.write(myarr.sort(sortNum));
</script>
<script type="text/javascript">
? ?function sortNum(a,b) {
return b-a;
? ?}
var myarr = new Array("80","16","50","6","100","1");
document.write(myarr.sort(sortNum));
</script>
2016-08-05
舉報
2016-08-05
加了括號就直接調(diào)用執(zhí)行那個函數(shù)了,結(jié)果為空,然后再執(zhí)行
? ? ? ? ? ? document.write(myarr.sort())
結(jié)果就是 ??1,100,16,50,6,80 ?
不加括號,sort()則按照所指定的方法排序
結(jié)果為 ?100,80,50,16,6,1
2016-08-05
從c語言函數(shù)角度來說的話,sort()函數(shù)需要時函數(shù)指針,